Heap / Priority Queue

You are playing the following Nim Game with your friend: * Initially, there is a heap of stones on the table. * You and your friend will alternate taking turns, and **you go first**. * On each

Alice plays the following game, loosely based on the card game **"21 "**. Alice starts with `0` points and draws numbers while she has less than `k` points. During each draw, she gains an integer num

Design a Leaderboard class, which has 3 functions: 1. `addScore(playerId, score)`: Update the leaderboard by adding `score` to the given player's score. If there is no player with such id in the lea

You are given a 2D `matrix` of size `m x n`, consisting of non-negative integers. You are also given an integer `k`. The **value** of coordinate `(a, b)` of the matrix is the XOR of all `matrix[i][j]